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تسجيل مستخدم جديدAn Improved Measurement of Neutrino Oscillation Parameters by the NOvA Experiment
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We present new $ u_murightarrow u_e$, $ u_murightarrow u_mu$, $overline{ u}_murightarrowoverline{ u}_e$, and $overline{ u}_murightarrowoverline{ u}_mu$ oscillation measurements by the NOvA experiment, with a 50% increase in neutrino-mode beam exposure over the previously reported results. The additional data, combined with previously published neutrino and antineutrino data, are all analyzed using improved techniques and simulations. A joint fit to the $ u_e$, $ u_mu$, $overline{ u}_e$, and $overline{ u}_mu$ candidate samples within the 3-flavor neutrino oscillation framework continues to yield a best-fit point in the normal mass ordering and the upper octant of the $theta_{23}$ mixing angle, with $Delta m^{2}_{32} = (2.41pm0.07)times 10^{-3}$ eV$^2$ and $sin^2theta_{23} = 0.57^{+0.03}_{-0.04}$. The data disfavor combinations of oscillation parameters that give rise to a large asymmetry in the rates of $ u_e$ and $overline{ u}_e$ appearance. This includes values of the CP-violating phase in the vicinity of $delta_text{CP} = pi/2$ which are excluded by $>3sigma$ for the inverted mass ordering, and values around $delta_text{CP} = 3pi/2$ in the normal ordering which are disfavored at 2$sigma$ confidence.
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